1. Field of the Invention
This invention relates to thread feeders for knitting machines, and more particularly, to a thread feeder having a feeding wheel capping with a thread-twisting preventive device to prevent broken threads from being pulled by and twisted around spinning parts of the thread feeder.
2. Description of Related Art
In knitting machines, a thread feeder is used to supply threads from a spool to the needles knitting a fabric. The smooth feeding of the threads is usually a primary consideration in designing the thread feeder. During the knitting process, however, the threads may break off due to various reasons. Once this happens, the broken threads could be pulled by and twisted around spinning parts of the thread feeder in a messy mass.
This problem is depicted in more details in the following with reference to FIG. 3. The conventional thread feeder shown in FIG. 3 includes a thread feeding wheel W on the bottom and a pulley set on the top. The bottom of the thread feeding wheel W is separated from the frame of the thread feeder by a space S, and the top the pulley set is separated from the same by a space of S1, as illustrated in FIG. 3.
If the thread breaks off at a point near the thread feeding wheel and yarn braking means P, the top portion of the broken thread, since it is still being rolled forwards, could be pulled by the exposed portions of the spinning axis in the neck portion N of the thread feeding wheel W as wall as in the neck portion N1 of the pulley set, and thus twisted around the same in a messy mass that could force the knitting machine to stop operation. Since the spaces S, S1 are very narrow in dimension, the twisted threads therein are very difficult to clear away. When doing the clearing, the knitting machine should be temporarily stopped, which will significantly affect the schedule of the production process.
In view of the foregoing problem in conventional knitting machines, there exists, therefore, a need for an improved thread feeder which is capable of preventing broken threads from being pulled by and twisted around spinning parts of the knitting machine such that the knitting machine will not be forced to stop for a long while so as to clear away the twisted mess of the broken threads.